Induction of ovarian growth and ovulation by administration of a chicken gonadotrophin preparation to Japanese quail kept under a short-day regimen.

1. Chronic administration of a glycoprotein fraction from chicken pituitary using an ALZET osmotic pump at 12.5 micrograms/h for 2 weeks induced growth of ovarian follicles to a mature size in the ovary and deposition of yolk in sexually immature 6-week-old Japanese quail females which were kept under 8L:16D short-day conditions. However, no ovulation was induced in these birds. 2. Injection of 500 micrograms of the glycoprotein into other immature short-day females was performed following the above chronic administration, 12 or 14 and 15 d after implantation of the osmotic pump. About 24 h after injection, 3 of 14 females laid one or two eggs. Ovulation was confirmed in 4 females by autopsy. A total of 5 of 14 females ovulated 6 eggs, and significant development of the oviduct and the cloacal opening were observed in all of the treated females. 3. Thus, complete ovarian function could be induced in sexually immature female Japanese quail by administration of avian gonadotrophin using a combination of an osmotic pump and an injection.     

Intranasal infection of Getah virus in experimental horses.

Aerosol transmission in equine Getah virus (GV) infection was examined by intranasal inoculation with 10(3.0) to 10(7.0) TCID50 of the MI-110 strain in 7 experimental horses. The establishment of intranasal infection of GV was confirmed in all these horses by detecting serum neutralizing antibody against the MI-110 strain. Horses inoculated with more than 10(4.0) TCID50 of the virus manifested mild pyrexia, eruptions, serous nasal discharge, lymphopenia or monocytosis. Viremia ranging from 10(1.0) to 10(3.5) TCID50/0.2 ml occurred in horses inoculated with 10(5.0) TCID50, or more. Virus recovery from the nasal cavity was observed only in horses inoculated with 10(7.0) TCID50, and the viral titers recorded were 10(3.0) TICD50/ml or less. From these results, it is assumed that GV disseminated from the nasal cavity of naturally infected horses, except for intranasal infection with a lot of the virus, is probably very low in titer. So it seems to be rare that GV in natural cycles is spread from horse to horse by aerosol transmission.     

EDEM as an acceptor of terminally misfolded glycoproteins released from calnexin

Terminally misfolded proteins in the endoplasmic reticulum (ER) are retrotranslocated to the cytoplasm and degraded by proteasomes through a mechanism known as ER-associated degradation (ERAD). EDEM, a postulated Man8B-binding protein, accelerates the degradation of misfolded proteins in the ER. Here, EDEM was shown to interact with calnexin, but not with calreticulin, through its transmembrane region. Both binding of substrates to calnexin and their release from calnexin were required for ERAD to occur. Overexpression of EDEM accelerated ERAD by promoting the release of terminally misfolded proteins from calnexin. Thus, EDEM appeared to function in the ERAD pathway by accepting substrates from calnexin.     

Physiological difference between free and triglyceride-type conjugated linoleic acid on the immune function of C57BL/6N mice

Previous studies have shown the physiological significance of dietary conjugated linoleic acid (CLA) in various experimental animals and in human beings. One of the important problems to better elucidate is the difference between triglyceride (TG) and free (FFA) dietary CLA. Here, using splenocytes, this study assesses how TG- and FFA-CLA modulate immunoglobulin and various cytokine productions. In this study, C57BL/6N mice were fed an experimental diet containing 0% CLA, 0.1 or 1% FFA-CLA, or 0.1 or 1% TG-CLA for 3 weeks. The production of immunoglobulin tended to be up-regulated by 1% FFA-CLA. As a result of protein array analysis using the supernatant from splenocytes cultured with no CLA, 1% FFA-CLA, and TG-CLA, some cytokine production was shown to be remarkably regulated by dietary FFA- and TG-CLA. A total of 32 cytokines were examined, and 11-14 produced cytokines that were 2-fold up-regulated as compared with control for FFA- or TG-CLA, respectively. Especially, the production of IL-9 and MCP-5 and other cytokines was remarkably up-regulated by both FFA- and TG-CLA. In addition, seven cytokines were 2-fold down-regulated by TG-CLA. These data show that there is a slight but significant difference between the functionalities of FFA- and TG-CLA.     

Studies on the organo-mineral colloidal complexes of paddy soil II

In the preceding paper (1) the authors reported the humus status in the organo-mineral colloidal complexes of the degraded paddy soils, which is characterized by the leaching of active iron, manganese and the other elements such as silica, magnesium and phosphoric acid from the furrow slice (2). And it was concluded that the organo-mineral colloidal complexes (Gl colloidal complexes) of the degraded paddy soil is characterized by the marked accumulation of humus, especially the readily soluble humus as compared with those of the normal.     

Effectiveness of tetrazolium salts in microbial ecological studies in submerged soil

Several trials to obtain information on the living microorganisms at micro-sites of the submerged soil by the novel utilization of the tetrazolium salts were described. Results are summarized as follows:

(1) The air-dried soil was incubated with TIC (triphenyl tetrazolium chloride) under submerged condition according to the modified double layer plate method. The red formazan (the reduced product of TIC) was precipitated at the biologically active sites by the dehy. drogenase activity. Using a binocular microscope, most of the biologically active sites were found to be localized on and around the organic debris.

(2) The amount of nitrogen mineralized by incubating the soil under submerged condi. tion correlated well not only with the amount of formazan formed biologically in the submerged soil but also with the amount of formazan formed non-biologically by heating the soil with TIC in Ba(OH). solution. In addition, the pattern of precipitation of the nonbiologically formed formazan was very similar to that of the biologically formed formazan. Accordingly, the substances which reduced TIC non-biologically were considered to be closely associated with the substrates for the microorganisms.

(3) The plant debris stained with the red formazan could be mounted on a slide glass and observed at high magnification for the detailed study on the process of decomposition. Addition of lactophenol cotton blue to the plant debris could visualize the microorganisms responsible for the decomposition of the plant debris.

(4) NTB (nitro tetrazolium blue) was the most suitable for staining individual microorganisms growing on cellulosic materials or plant debris. The double staining with NTB and rosebengal made the discrimination between dead or resting cells and viable ones possible when this technique was applied to the decomposed filter paper.     

Nitrogen isotope fractionation during nitrogen transport from ectomycorrhizal fungi,Suillus granulatus,to the host plant,Pinus densiflora

The ¹⁵N natural abundance in Pinus densiflora Sieb. et Zucco that had been inoculated and not inoculated with ectomycorrhizal fungi (Suillus granulatus (L.:Fr.) O. Kuntze) was compared. The inoculated pine needles showed a lower δ¹⁵N value, while the uninoculated ones showed a higher δ¹⁵N value. Higher δ¹⁵N values in the mycelial mat of the ectomycorrhizal fungi compared to those of the inoculated pine needles were also observed. These facts indicate that nitrogen isotope fractionation occurred during the nitrogen transport from mycorrhizal fungi to the host plants.